Communications network providers such as AT&T typically offer an array of communications service features. Each feature can be automatically provided to those users that subscribe to that feature. An example of such a communications service feature is Positive Call Processing (PCP) offered by AT&T. One aspect of PCP service lets a user enter an account code when making a long distance call. The account code appears on the user's monthly bill along with other billing information, letting the user segregate the cost of certain calls and perhaps pass along that cost to a third party. For example, a user could enter a five digit account code representing a certain client when making long distance calls on behalf of that client. At the end of the month, the user's long distance telephone bill would list all calls made with that account code together with the total cost of those calls. The user could then ask the client to pay the cost of those long distance telephone calls. Another aspect of PCP service allows employers to limit the types of non-local telephone calls made by employees. An employer could, for example, prevent some employees from dialing international telephone numbers while preventing other employees from making any non-local telephone calls.
When a communication is initiated by a user, the network provider must determine if that user subscribes to one or more communications service features. In the Public Switched Telephone Network (PSTN), this is typically done at the communications switch that routes telephone calls from the user's geographic region as reflected by the user's Numbering Plan Area (NPA) code, or “area code.” This communications switch is commonly called the originating switch. Each originating switch contains a list, or table, of subscribers normally served by the switch. A single switch can route calls from several area codes, so a table of subscribers in an originating switch can include subscribers in any of several area codes served by that switch. When a communication is initiated by a user, the originating switch looks up that user's telephone number in the subscriber table to determine if the user subscribes to a communications service feature. If the user is a subscriber the communications service feature is then provided.
A problem arises when the owner of a wireless telephone wishes to subscribe to a communications service feature. The term “wireless” includes both cellular and Personal Communication Services (PCS) based communications. As long as the telephone is used within the geographic location covered by that telephone's normal originating switch, the originating switch can look up that user's telephone number in the subscriber table to determine if the user is a subscriber. If, however, the wireless telephone travels, or “roams,” outside the geographic location served by that telephone's normal originating switch, the call will be routed through a different communications switch. Because the user's telephone number will not appear in the subscriber table maintained in the different switch, the different switch cannot recognize that the user is a subscriber and the communications service feature will not be provided. This is undesirable because users are generally not aware of switching system details and will not understand why the system is “not working.” Moreover, a user of a wireless telephone who frequently travels outside the geographic location served by that telephone's normal originating switch will not be able to enjoy the benefits of communications service features.
To overcome this problem, a network provider can maintain a database of the telephone numbers of every subscriber, regardless of geographic location. Unfortunately, due to the large volume of telephone calls handled by a provider it is not practical to query a database of subscriber telephone numbers for every telephone call.
Another complication is that a long distance wireless telephone call may originally be routed in another provider's network. For example, in wireless networks an electronic switching system called the Mobile Telephone Switching Office (MTSO) or Mobile Switching Center (MSC) provides call-processing for users in a particular geographic region. The MTSO/MSC communicates with a user's wireless telephone through a set of base stations and will typically route a long distance call to a long distance network provider. The MTSO/MSC also forwards calls directed to a wireless user through a long distance network provider if the wireless user is located outside of their home geographic region. In this case, the user receiving the call, not the party making the call, pays for the long distance service. Therefore, the MTSO/MSC associates the user's telephone number with the call when routing it through the long distance network provider. Because of this, when a call is routed from a MTSO/MSC it is possible that the long distance network provider will not even know the telephone number of the user making the call.
With respect to PCP service, the problem is also complicated by the fact that the user's network provider may not control the billing records for a particular long distance wireless telephone call. Control of the billing records in such a situation is also called “recording take back.” In this case, it would not make sense to provide the user with PCP service because account code information would not appear on the user's telephone bill, a main feature of PCP service.
In view of the foregoing, it can be appreciated that a substantial need exists for a method and apparatus for providing a communications service feature, such as PCP service, for a communication through a network, such as a long distance wireless telephone call.